Discussion:
Morphological variation in placenta is not so uncommon. The variation in
anatomy of placenta and its associated vessels frequently complicate
normal labor. Various individual, genetic as well as environmental
factors interplay in causation of the variation in the placenta. [4]
Succenturiate lobe is also a clinically significant morphological
variation of placenta arising as a result of interplay between these
factors. There are different hypothesis supporting the formation of the
succenturiate lobe of placenta. One of the hypotheses emphasizes that a
small island of normal villous tissue remains at a distance from the
main lobe of placenta forming the succenturiate lobe as the villous
tissue between the two lobes atrophies. Other hypothesis states that
succenturiate lobe is created when ovum is implanted between sulcus
between two walls of the uterus. [4, 5] Succenturiate lobe of
placenta can be suspected in time by ultrasonography. However,
confirmation of presence of succenturiate lobe by ultrasonography is
rare. It is a very challenging task to confirm the findings and requires
ruling out conditions like multiple pregnancy, structures like amniotic
band and uterine septum. [1, 4]
In this case, presence of succenturiate lobe of placenta was suspected
beforehand during antenatal ultrasonography at 34 weeks of gestation and
was taken into consideration for emergency cesarean section leading to
otherwise uneventful delivery of a healthy fetus.